System and method for radio link sharing

ABSTRACT

In one embodiment, a method includes receiving, by a first user equipment (UE) from a second UE, identity information and transmitting, by the first UE to a communications controller, the identity information. The method also includes receiving, by the first UE from the communications controller, a first packet after transmitting the identity information and transmitting, by the first UE to the second UE, the first packet in accordance with the identity information.

TECHNICAL FIELD

The present invention relates to a system and method for wirelesscommunications, and, in particular, to a system and method for radiolink sharing.

BACKGROUND

A single person may have access to more than one user equipment (UE),such as wearable devices, tablets, smartphones, mobile wireless routers,and other devices. These UEs have their own identity and may beconnected to a wireless wide area network (WWAN) and a local network,such as a wireless local area network (WLAN) or personal area network(PAN), or through WiFi. Each UE may not have the same access to WWAN.For example, some UEs may be in a disadvantaged position with a poorradio link, for example from a blocked signal or poor radio frequency(RF) front end, less supported band, or worse radio access technology.Some UEs may be in a better location, may be supported by a widerbandwidth, have better access technology, or less of a constraint onpower consumption.

Also, some UEs may have multiple subscriber identity module (SIM) cardslots, which support multiple phone calls simultaneously. For example,in dual SIM dual active (DSDA) or dual SIM dual standby (DSDS) enablesone UE to register a network with multiple identifiers, or multipleSIMs.

SUMMARY

An embodiment method includes receiving, by a first user equipment (UE)from a second UE, identity information and transmitting, by the first UEto a communications controller, the identity information. The methodalso includes receiving, by the first UE from the communicationscontroller, a first packet after transmitting the identity informationand transmitting, by the first UE to the second UE, the first packet inaccordance with the identity information.

An embodiment method includes transmitting, by a first user equipment(UE) to a second UE, identity information and receiving, by the first UEfrom the second UE, a first message indicating that the first UE hasbeen added to a first network after transmitting the identityinformation. The method also includes transmitting, by the first UE tothe second UE after receiving the first message, a first packet inaccordance with the identity information, where the first packet isdestined for the first network.

An embodiment first user equipment (UE) includes a processor and anon-transitory computer readable storage medium storing programming forexecution by the processor. The programming includes instructions toreceive, from a second UE, identity information and transmit, to acommunications controller, the identity information. The programmingalso includes instructions to receive, from the communicationscontroller, a first packet after transmitting the identity informationand transmit, to the second UE, the first packet in accordance with theidentity information.

An embodiment first user equipment (UE) includes a processor and anon-transitory computer readable storage medium storing programming forexecution by the processor. The programming including instructions totransmit, to a second UE, identity information and receive, from thesecond UE, a first message indicating that the first UE has been addedto a first network after transmitting the identity information. Theprogramming also includes instructions to transmit, to the second UEafter receiving the first message, a first packet in accordance with theidentity information, where the first packet is destined for the firstnetwork.

An embodiment method includes receiving, by a first user equipment (UE)from a second UE, an international mobile subscriber identity (IMSI) ofa subscriber identity module (SIM) card of the second UE andtransmitting, by the first UE to a communications controller, the IMSIof the SIM card of the second UE. The method also includes receiving, bythe first UE from the communications controller, a first packet using aSIM card of the first UE, after transmitting the IMSI of the SIM card ofthe second UE and transmitting, by the first UE to the second UE, thefirst packet in accordance with the IMSI of the SIM card of the secondUE.

An embodiment method includes transmitting, by a first user equipment toa second UE, an international mobile subscriber identity (IMSI) of asubscriber identity module (SIM) card of the first UE and receiving, bythe first UE from the second UE, a message indicating that the first UEhas been added to a first network after transmitting the IMSI of the SIMcard of the first UE. The method also includes receiving, by the firstUE from the second UE, after receiving the message, a packet, inaccordance with the IMSI of the SIM card of the first UE, where thepacket is from the first network.

The foregoing has outlined rather broadly the features of an embodimentof the present invention in order that the detailed description of theinvention that follows may be better understood. Additional features andadvantages of embodiments of the invention will be describedhereinafter, which form the subject of the claims of the invention. Itshould be appreciated by those skilled in the art that the conceptionand specific embodiments disclosed may be readily utilized as a basisfor modifying or designing other structures or processes for carryingout the same purposes of the present invention. It should also berealized by those skilled in the art that such equivalent constructionsdo not depart from the spirit and scope of the invention as set forth inthe appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawing, in which:

FIG. 1 illustrates a diagram of a wireless network for communicatingdata;

FIG. 2 illustrates an embodiment system for radio link sharing;

FIG. 3 illustrates another embodiment system for radio link sharing;

FIG. 4 illustrates an additional embodiment system for radio linksharing;

FIG. 5 illustrates an embodiment method of radio link sharing performedby a user equipment (UE);

FIG. 6 illustrates another embodiment method of radio link sharingperformed by a UE; and

FIG. 7 illustrates a block diagram of an embodiment computer system.

Corresponding numerals and symbols in the different figures generallyrefer to corresponding parts unless otherwise indicated. The figures aredrawn to clearly illustrate the relevant aspects of the embodiments andare not necessarily drawn to scale.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

It should be understood at the outset that although an illustrativeimplementation of one or more embodiments are provided below, thedisclosed systems and/or methods may be implemented using any number oftechniques, whether currently known or in existence. The disclosureshould in no way be limited to the illustrative implementations,drawings, and techniques illustrated below, including the exemplarydesigns and implementations illustrated and described herein, but may bemodified within the scope of the appended claims along with their fullscope of equivalents.

An embodiment method involves sharing radio links between userequipments (UEs) through an internet protocol (IP) network. One UE, arequester UE, finds a better situated UE which supports multiplesubscriber identity modules (SIMs) to act as a donor UE to relay thedata and voice packets between the network and the requesting UE. Therequester UE's tunneling identity information is tunneled through the IPnetwork to the donor UE. Then, the requester UE communicates with thenetwork through the donor UE.

FIG. 1 illustrates network 100 for communicating data. Network 100includes communications controller 102 having a coverage area 106, aplurality of UEs, including UE 104 and UE 105, and backhaul network 108.Two UEs are depicted, but many more may be present. Communicationscontroller 102 may be any component capable of providing wireless accessby establishing uplink (dashed line) and/or downlink (dotted line)connections with UE 104 and UE 105, such as a base station, a NodeB, anenhanced nodeB (eNB), an access point, a picocell, a femtocell, andother wirelessly enabled devices. UE 104 and UE 105 may be any componentcapable of establishing a wireless connection with communicationscontroller 102, such as cell phones, smart phones, tablets, sensors,etc. Backhaul network 108 may be any component or collection ofcomponents that allow data to be exchanged between communicationscontroller 102 and a remote end. In some embodiments, the network 100may include various other wireless devices, such as relays, etc.

FIG. 2 illustrates system 110 for remotely sharing a radio link. UE 118,the requester UE, UE 122, and access point 120 are in area 116.Initially UE 118 communicates with communications controller 112.However, the link between UE 118 and communications controller 112becomes a bad link. UE 118 loses network coverage, and enters anout-of-service state.

Then, UE queries other UEs for capability and link status (signalquality) to search for another UE to act as a donor UE. The delay fromrelaying may be considered in determining whether an appropriate qualityof service (QoS) may be achieved. The level of SIM support is alsoconsidered in selecting a donor UE. UE 118 may use WiFi, Bluetooth,local wireless IP on top of WLAN, a personal area network (PAN), a localarea network (LAN) through an access point to a wired IP network, amixed IP network with wireless and wired elements, or another auxiliarynetwork. UE 118 may send a request for a donor UE to access point 120,which broadcasts this request. UE 122 and UE 114 receive this request.UE 122 is not a suitable donor UE, and responds with its unavailabilityor with its characteristics, or it ignores the request. On the otherhand, UE 114 is available to relay information from UE 118. UE 114supports multiple SIMS, for example dual SIM dual active (DSDA), dualSIM dual standby (DSDS), triple SIM triple active (TSTA), triple SIMtriple standby (TSTS) capable, or a higher SIM level, and has a goodlink with communications controller 112. UE 114 may use one local SIMand one remote virtual SIM may be used. In one example, UE 118 and UE114 have a relationship. For example, they are owned by the sameindividual, or by family members, friends, colleagues, or an employer.The donor UE may request a PIN to authenticate the requester UE, or useanother method, such as hardware identification (ID), IMSI, phonenumber, etc. to control the access. UE 114 responds with its acceptance,either directly or with its characteristics, to access point 120, whichforwards it to UE 118.

Next, UE 118 transmits identity information, for example theinternational mobile subscriber identity (IMSI), along with a list ofservices that the UE has access to, from the SIM or other subscriberidentity modules, such as universal SIM (USIM), a removable useridentity module (R-UIM), or universal integrated circuit card (UICC), toUE 114. UE 114 uses the identity information from UE 118 to register UE118 to the second network through itself. SIM is an integrated circuitwhich stores the IMSI and the related information used to identify andauthenticate subscribers. A SIM circuit is embedded in a removableplastic card, or SIM card, which may be transferred between differentmobile devices. A SIM card contains a unique serial number or integratedcircuit card identifier (ICCID), an IMSI, security authentication andciphering information, temporary information related to the localnetwork, a list of the services the user has access to and twopasswords, a personal identification number (PIN) for and a personalunblocking code (PUK) for unlocking the PIN. SIM cards store networkspecific information used to authenticate and identify subscribers in anetwork, including the ICCID, IMSI, the authentication key (K_(i)),local area identity (LAI), and an operator specific emergency number.The IMSI is used to connect mobile phone calls. The IMSI includes amobile country code (MCC), a mobile network code (MNC), and mobilesubscriber identification number (MSIN). Also, the authentication key isa 128 bit value used to authenticate SIMs on a mobile network. A SIM hasa unique authentication key assigned during personalization. Theauthentication key is also stored in a database or authentication centeron the carrier's network. A SIM card has a function run global systemfor mobile communications (GSM) algorithm which allows the phone to passdata to the SIM card to be signed with the authentication key. UE 118transmits the IMSI retrieved from its SIM card to UE 114, whichtransmits this to the network via communications controller 112. Thenetwork searches its database for the incoming IMSI and associatedauthentication key. Next, the operator generates a random number (RAND),which is a nonce, and signs it with the authentication key associatedwith the IMSI. Also, signed response 1 (SRES_1) is computed by thenetwork. The network transmits the RAND to UE 114 via communicationscontroller 112, and UE 114 forwards the RAND to UE 118. The SIM card ofUE 118 signs the RAND with its authentication key K_(i), producingsigned response 2 (SRES_2), which it transmits to UE 114, and UE 114forwards SRES_2 to the network via communications controller 112. Thenetwork compares SRES_1 and SRES_2. Upon receiving the RAND, UE 118 alsocreates an encryption key K_(c). When the two signed responses match,the SIM is authenticated, and UE 118 is granted access to the networkvia UE 114. On the other hand, when the two numbers do not match, accessis denied.

After UE 118 has been added to the network, UE 118 communicates with thenetwork through UE 114 and communications controller 112 using theencryption key K_(c). The donor UE may use one local SIM and one remotevirtual SIM. UE 118 may have a mobile phone call with the voice packetsrouted through UE 114 and communications controller 112. Buffering maybe used to smooth voice jitter. In another example, UE 118 transmits andreceives data to communications controller 112 via UE 114. Mobileoriginating (MO) and mobile terminating (MT) calls may be relayedthrough the donor UE to the requester UE.

When the signal quality of UE 118 improves, the link through UE 114 maybe disconnected and a direct link is added. UE 118 may ask UE 114 tode-register UE 118 from the network. UE 118 may signal to the network tode-register itself via UE 114, and notify UE 114 upon the completion ofde-registration. Then, UE 118 registers itself to the new network, andcommunicates with the network without UE 114.

FIG. 3 illustrates system 130, another system which may be used for UEradio link sharing. UE 138 is in a coverage area with an available datarate lower than its desired data rate. For example, UE 138 may be insecond generation of mobile telecommunications technology (2G) servicearea 139 and desire third generation of mobile telecommunicationstechnology (3G) or fourth generation of mobile telecommunicationstechnology (4G) service. In another example, UE 140 is 3G service area136, but desires 4G service. In an additional example, the requester UEis in a 4G service area and wants fifth generation of mobiletelecommunications technology (5G) service. UE 138 queries other UEsthrough an auxiliary network connection to find a donor UE.

Then, UE 138 queries other UEs for capability or link status to find adonor UE. The donor UE should also support multiple SIMs. The delay intunneling through the donor UE is also considered. UE 138 may use WiFi,Bluetooth, local wireless IP on top of WLAN, a PAN, a LAN, an auxiliarywireless IP network, through an access point to a wired IP network, amixed IP network with wireless and wired elements, or another network.To search for a donor UE, UE 138 transmits a request for a donor UE toaccess point 144, which broadcasts this request. UE 140 and UE 134receive the request. UE 140 has 3G service, which may not be sufficientto warrant link sharing. UE 140 may respond with its 3G status or itsunavailability, or it may ignore the request. On the other hand, UE 134has 4G service and is available to serve as a donor UE. UE 134 hasmultiple SIM capability, such as DSDA, DSDS, TSTA, TSTS, or a higherlevel SIM capability, and has a good link with communications controller132. UE 138 and UE 134 may have a relationship, such as being are ownedby the same individual, or by family members, friends, by a commonemployer, colleagues, or another relationship. Donor UE responds withits acceptance to access point 144, who forwards it to UE 138.

Then, UE 138 de-registers from its current 2G network. UE 138 transmitsa message to the network which UE 138 is currently using, through accesspoint 144 requesting to be de-registered from the network. The networkde-registers UE 138, and transmits an acknowledgment message to UE 138via access point 144.

Next, UE 138 transmits identity information, such as the IMSI, alongwith a list of services that the UE has access to, from the SIM oranother identity module, to UE 134, which uses the identity informationfrom UE 138 to register UE 138 to the network. UE 138 transmits the IMSIretrieved from its SIM card to UE 134, which transmits the IMSI to thenetwork via communications controller 132. The network searches itsdatabase for the incoming IMSI and associated authentication key. Next,the network generates a RAND, which is a nonce, and signs it with theauthentication key associated with the IMSI. Also, SRES_1 is computed bythe network. The network then transmits the RAND to UE 134 viacommunications controller 132, and UE 134 forwards the RAND to UE 138.The SIM card of UE 138 signs the RAND with its authentication key,producing SRES_2, which it transmits to UE 134. Next, UE 134 forwardsSRES_2 to the network via communications controller 132, and the networkcompares SRES_1 and SRES_2. Upon receiving the RAND, UE 138 also createsan encryption key K_(c). When the two numbers match, the SIM isauthenticated, and UE 138 is granted access to the operator network viaUE 134. When the two numbers do not match, access is denied.

Finally, UE 138 communicates with the network through UE 134 andcommunications controller 132 using the encryption key K_(c). UE 138 mayhave a mobile phone call with the voice packets, data packets, and/ornetwork access stratum (NAS) signaling from MO and MT calls are routedthrough UE 134 and communications controller 132 using the auxiliary IPnetwork. Buffering may be used to smooth voice jitter for voice packets.

When UE 138 enters a better service area, for example an area with 3G,4G, 5G, or a higher level coverage, the link through UE 134 ends. UE 138transmits a message to UE 134 to de-register UE 138 from the network.For example, UE 134 transmits a message to the network viacommunications controller 132, the network de-registers UE 138, andresponds with an acknowledgment message. UE 138 may signal the networkand de-register itself via UE 134, and notify UE 134 upon the completionof de-registration. Then, UE 138 registers itself to the new network,and communicates with this network without use of UE 134.

FIG. 4 illustrates system 150, an additional system, for UE radio linksharing, which may be used to avoid roaming charges and facilitateauthentication in various situations, for example when accessing a bank.Also, the requestor UE may access a wireless wide area network (WWAN)network remotely when radio access technology (RAT) is not availablelocally. UE 162 is in area 154, with access to communications controller160. UE 162 either has no service or is roaming in area 154. However, UE162 has access to an auxiliary network, such as wireless or wired IPaccess.

UE 162 connects to UE 158 in area 152, which may be a home or preferredarea for UE 162, via a wireless or wired IP network. The requestor anddonor UEs may be in different geographic areas. In one example, UE 162is in another country, or in an area without cellular service but withanother form of IP service. UE 158 may have a relationship with UE 162.For example, UE 158 is a device with the same owner as UE 162, where UE158 is at a favored location, such as home, work, or the home of afamily member or friend. In another example, UE 158 is owned by a familymember, friend, or colleague of the user, and is with the family memberor friend at a favorable location. Donor UE may request a PIN toauthenticate the requestor UE, or use another method, such as hardwareID, IMSI, phone number, etc. to control the access.

Next, UE 162 transmits identity information, such as the IMSI, alongwith a list of services that the UE has access to, from the SIM oranother identity module, to UE 158, which uses the SIM information fromUE 162 to register UE 162 to the network. UE 162 transmits the IMSI, toUE 158, which then transmits it to the network via communicationscontroller 156. The network searches its database for the incoming IMSIand associated authentication key. Next, the network generates a RAND,which is a nonce, and signs it with the authentication key associatedwith the IMSI. Also, SRES_1 is computed by the operator network, whichtransmits the RAND to UE 158 via communications controller 156. UE 158then forwards the RAND to UE 162. The SIM card of UE 162 signs the RANDwith its authentication key, producing SRES_2, which it transmits to UE158. UE 158 forwards SRES_2 to the network via communications controller156. Upon receiving the RAND, UE 162 also creates an encryption keyK_(c). The operator network compares SRES_1 and SRES_2. When the twonumbers match, the SIM is authenticated, and UE 162 is granted access tothe operator network via UE 158. On the other hand, when the numbers donot match, access is denied.

Finally, UE 162 communicates with the network through UE 158 andcommunications controller 156 using the encryption key K_(c). UE 162 mayhave a mobile phone call with the voice packets, data packets, and/orNAS signaling from MO and MT calls are routed through UE 158 andcommunications controller 156 using the auxiliary network. Buffering maybe used to smooth voice jitter.

When UE 162 enters a better service area, the link through UE 158 ends.For example, UE 162 may enter a home network area or an area withcoverage. UE 162 asks UE 158 to de-register itself from the network. Forexample, UE 158 transmits a message to the network via communicationscontroller 156, the network de-registers UE 162, and responds with anacknowledgment message. UE 162 may signal the network and de-registeritself via UE 158, and notify UE 158 upon the completion of thede-registration. Then, UE 162 registers itself to the new network, andcommunicates with the network without UE 158.

FIG. 5 illustrates flowchart 170 for an embodiment method of remotelysharing a UE radio link performed by a requester UE. Initially, in step172, the requester UE determines that there is a service problem, anddecides to seek to share a link with a donor UE. The service problem maybe a lack of service, service with a data rate lower than the desireddata rate, roaming service, or another service problem, such asintermittent service.

Next, in step 176, the requester UE determines the identity of a donorUE. The requester UE may broadcast a message searching for a donor UEusing an auxiliary network, such as WiFi, Bluetooth, local wireless IPon top of WLAN, a PAN, a LAN, through an access point to a wired IPnetwork, a mixed IP network with wireless and wired elements, or anotherauxiliary network. Then, the requester UE may receive responses from UEsindicating whether they are able to serve as a donor UE, or withinformation for the requester UE to use to determine whether one of theUEs is a suitable donor UE. For example, link quality, delays, andrelationships may be considered. In another example, the requester UEhas a wired or wireless IP connection, and is already aware of a donorUE. The requester UE may specifically contact that UE requesting thatthe donor UE serve as a donor UE. The donor UE may reply with a messageagreeing to serve as the donor UE or with information on thecapabilities of the donor UE.

In step 182, the requester UE disconnects from its current network whenit is currently connected to a network. For example, the requester UEmay disconnect from a network which has poor services, for example 2G or3G service, when the requester UE desires 4G service.

In step 180, the requester UE joins the network through the donor UE.The requester UE transmits the IMSI to the donor UE. The requester UEreceives the RAND from the donor UE. The SIM card of the requester UEsigns the RAND with its authentication key, producing SRES_2, which ittransmits to the donor UE.

After joining the network through the donor UE, the requester UEtransmits and receives packets using the donor UE in step 174. Therequester UE transmits and receives packets to the donor UE, which thedonor UE forwards to and from the network using an encryption key.Various types of packets, such as voice packets, data packets, and/orNAS signaling from MO and MT, may be used.

In step 177, the requester UE determines whether good service isavailable for a network which it directly accesses. For example, therequester UE may enter a service area where it has some service, betterservice, or non-roaming service. When the requester UE does not detectgood service availability, it returns to step 174 and continues to relaypackets through the donor UE. When the requester UE detects goodservice, it proceeds to step 184.

In step 184, the requester UE disconnects from the network. Therequester UE transmits a message to the donor UE requesting to bedisconnected from the network. In response, the requester UE receives anacknowledgment that it has been disconnected from the network. Inanother embodiment, the requester UE notifies the network to de-registeritself, and notifies donor UE on completion on the de-registration.

Finally, in step 186, the requester UE joins the network directly, forexample through a communications controller. Then, the requestor UEcommunicates with the network through the communications controller.

FIG. 6 illustrates flowchart 190 for a method of sharing a radio linkperformed by a donor UE. Initially, in step 194, the donor UE agrees tobe a donor UE. The donor UE may receive a message from a requester UEasking the donor UE to serve as a donor UE. The donor UE may considerseveral factors in deciding whether to be a donor UE. For example, thedonor UE should have multiple SIM capacity and a good connection. Thedonor UE may also have a pre-existing relationship with the requesterUE. For example, the donor UE may be owned by the owner of the receiverUE, or by a family member, friend, or co-worker of the owner of therequester UE. The donor UE may also consider its own usage needs. Thedonor UE transmits a message to the requester UE indicating itswillingness to serve as a UE and/or one or more factors.

Next, in step 196, the donor UE adds the requester UE to the network.The donor UE receives identity information, such as SIM or USIMinformation, from the requester UE, and uses the SIM information toregister the requester UE to the network. Then the donor UE receives aRAND from the network, for example from the communications controller,which it forwards to the requester UE. In response, the donor UEreceives SRES_2 from the requester UE, which it forwards to the network.The donor UE receives, from the network, an acknowledgment that therequester UE has been added to the network, which it forwards to therequester UE.

After the requester UE has been added to the network through the donorUE, the donor UE relays data between the requester UE and the network instep 200 using the encryption key. A mobile phone call with the voicepackets, data packets, and/or NAS signaling from MO and MT calls arerouted through the donor UE. The donor UE receives packets from therequester UE which it forwards to the communications controller, andreceives packets from the communications controller which it forwards tothe requester UE. The donor UE may be performing its own tasks at thesame time.

In step 192, the donor UE determines whether it has received a requestfrom the requester UE to remove the requester UE from the network. Whenthere is no such request, the donor UE continues relaying packets instep 200. When the donor UE receives such a request, it proceeds to step202. In another embodiment, the requestor UE may de-register itself fromnetwork, and send a notification to the donor UE. Upon receiving thenotification, the donor UE proceeds to step 202.

In step 202, the donor UE disconnects the requester UE from the network.The donor UE may transmit a request to the communications controllerrequesting that the requester UE be removed from the network. When thedonor UE receives an acknowledgment response from the communicationscontroller, it forwards the acknowledgment to the requester UE. Then,the donor UE will release the resource reserved for the second SIM(virtual SIM) and continue to do its own tasks. In another embodiment,the requestor UE notifies the donor UE upon the completion of thede-registration, the donor UE releases the resources reserved for thesecond SIM, and continue its own tasks.

When the connection between the donor UE and requestor UE is lost, therequestor UE may start a timer. Upon the expiration of the timer, therequester UE may de-register the requester UE from the network.

When the donor UE's network and signal quality cannot support the donorUE's service, the requester UE may choose to de-register from thenetwork and search for a new donor UE.

FIG. 7 illustrates a block diagram of processing system 270 that may beused for implementing the devices and methods disclosed herein. Specificdevices may utilize all of the components shown, or only a subset of thecomponents, and levels of integration may vary from device to device.Furthermore, a device may contain multiple instances of a component,such as multiple processing units, processors, memories, transmitters,receivers, etc. The processing system may comprise a processing unitequipped with one or more input devices, such as a microphone, mouse,touchscreen, keypad, keyboard, and the like. Also, processing system 270may be equipped with one or more output devices, such as a speaker, aprinter, a display, and the like. The processing unit may includecentral processing unit (CPU) 274, memory 276, mass storage device 278,video adaptor 280, and I/O interface 288 connected to a bus.

The bus may be one or more of any type of several bus architecturesincluding a memory bus or memory controller, a peripheral bus, videobus, or the like. CPU 274 may comprise any type of electronic dataprocessor. Memory 276 may comprise any type of non-transitory systemmemory such as static random access memory (SRAM), dynamic random accessmemory (DRAM), synchronous DRAM (SDRAM), read-only memory (ROM), acombination thereof, or the like. In an embodiment, the memory mayinclude ROM for use at boot-up, and DRAM for program and data storagefor use while executing programs.

Mass storage device 278 may comprise any type of non-transitory storagedevice configured to store data, programs, and other information and tomake the data, programs, and other information accessible via the bus.Mass storage device 278 may comprise, for example, one or more of asolid state drive, hard disk drive, a magnetic disk drive, an opticaldisk drive, or the like.

Video adaptor 280 and I/O interface 288 provide interfaces to coupleexternal input and output devices to the processing unit. Asillustrated, examples of input and output devices include the displaycoupled to the video adapter and the mouse/keyboard/printer coupled tothe I/O interface. Other devices may be coupled to the processing unit,and additional or fewer interface cards may be utilized. For example, aserial interface card (not pictured) may be used to provide a serialinterface for a printer.

The processing unit also includes one or more network interface 284,which may comprise wired links, such as an Ethernet cable or the like,and/or wireless links to access nodes or different networks. Networkinterface 284 allows the processing unit to communicate with remoteunits via the networks. For example, the network interface may providewireless communication via one or more transmitters/transmit antennasand one or more receivers/receive antennas. In an embodiment, theprocessing unit is coupled to a local-area network or a wide-areanetwork for data processing and communications with remote devices, suchas other processing units, the Internet, remote storage facilities, orthe like.

While several embodiments have been provided in the present disclosure,it should be understood that the disclosed systems and methods might beembodied in many other specific forms without departing from the spiritor scope of the present disclosure. The present examples are to beconsidered as illustrative and not restrictive, and the intention is notto be limited to the details given herein. For example, the variouselements or components may be combined or integrated in another systemor certain features may be omitted, or not implemented.

In addition, techniques, systems, subsystems, and methods described andillustrated in the various embodiments as discrete or separate may becombined or integrated with other systems, modules, techniques, ormethods without departing from the scope of the present disclosure.Other items shown or discussed as coupled or directly coupled orcommunicating with each other may be indirectly coupled or communicatingthrough some interface, device, or intermediate component whetherelectrically, mechanically, or otherwise. Other examples of changes,substitutions, and alterations are ascertainable by one skilled in theart and could be made without departing from the spirit and scopedisclosed herein.

What is claimed is:
 1. A method comprising: receiving, by a first userequipment (UE) from a second UE, identity information, wherein theidentity information comprises subscriber identity module (SIM)information of the second UE; registering, by the first UE, the secondUE to a network by transmitting the identity information to acommunications controller; receiving, by the first UE from thecommunications controller, a first packet, after registering the secondUE to the network; and transmitting, by the first UE to the second UE,the first packet in accordance with the SIM information of the secondUE.
 2. The method of claim 1, further comprising: receiving, by thefirst UE from the communications controller, a random number, afterreceiving the identity information; transmitting, by the first UE to thesecond UE, the random number; receiving, by the first UE from the secondUE, a signed random number; and transmitting, by the first UE to thecommunications controller, the signed random number.
 3. The method ofclaim 1, further comprising: receiving, by the first UE from the secondUE, after transmitting the identity information, a second packet; andtransmitting, by the first UE to the communications controller, thesecond packet.
 4. The method of claim 1, further comprising: receiving,by the first UE from the second UE, a first message requesting radiolink sharing; and transmitting, by the first UE to the second UE, aftertransmitting the first message and before receiving the identityinformation, a second message, wherein the second message indicates acapability of the first UE to serve as a donor UE.
 5. The method ofclaim 1, wherein the first packet is a voice packet.
 6. The method ofclaim 1, wherein the first packet is a data packet.
 7. A methodcomprising: transmitting, by a first user equipment (UE) to a second UE,identity information, wherein the identity information comprisessubscriber identity module (SIM) information of the first UE; receiving,by the first UE from the second UE, a first message indicating that thefirst UE has been added to a first network, after transmitting theidentity information; and transmitting, by the first UE to the secondUE, after receiving the first message, a first packet in accordance withthe SIM information of the first UE, wherein the first packet isdestined for the first network.
 8. The method of claim 7, furthercomprising accessing an international mobile subscriber identity (IMSI)of a subscriber identity module (SIM) card of the first UE, wherein theidentity information comprises the IMSI.
 9. The method of claim 8,further comprising: receiving, by the first UE from the second UE, arandom number, after transmitting the identity information; signing therandom number, to produce a signed random number; and transmitting, bythe first UE to the second UE, the signed random number.
 10. The methodof claim 7, further comprising receiving, by the first UE from thesecond UE, after receiving the first message, a second packet, whereinthe second packet originates from the first network.
 11. The method ofclaim 7, further comprising: transmitting, by the first UE to the secondUE, a second message requesting radio link sharing before transmittingthe identity information; receiving, by the first UE from the second UE,after transmitting the second message, a third message indicating acapability of the second UE to serve as a donor UE; and determiningwhether the second UE will serve as the donor UE in accordance with thethird message, wherein transmitting the identity information is onlyperformed after determining that the second UE will serve as the donorUE.
 12. The method of claim 7, further comprising detecting a networkproblem before transmitting the identity information.
 13. The method ofclaim 12, wherein the network problem is a lack of service.
 14. Themethod of claim 12, wherein the network problem is that the networkimposes charges on the first UE.
 15. The method of claim 12, wherein thenetwork problem is that an available data rate of the network is lowerthan a target data rate of the first UE.
 16. The method of claim 7,further comprising: searching for a second network; determining whetherthe second network provides good service to the first UE; disconnectingfrom the first network, upon determining that the second networkprovides good service to the first UE; and connecting to the secondnetwork after disconnecting from the first network.
 17. A first userequipment (UE) comprising: a processor; and a non-transitory computerreadable storage medium storing programming for execution by theprocessor, the programming including instructions to: receive, from asecond UE, identity information, wherein the identity informationcomprises subscriber identity module (SIM) information of the second UE,register the second UE to a network by transmitting the identityinformation to a communications controller, receive, from thecommunications controller, a first packet, after registering the secondUE to the network, and transmit, to the second UE, the first packet inaccordance with the SIM information of the second UE.
 18. A first userequipment (UE) comprising: a processor; and a non-transitory computerreadable storage medium storing programming for execution by theprocessor, the programming including instructions to: transmit, to asecond UE, identity information, wherein the identity informationcomprises subscriber identity module (SIM) information of the first UE,receive, from the second UE, a first message indicating that the firstUE has been added to a first network, after transmitting the identityinformation, and transmit, to the second UE after receiving the firstmessage, a first packet in accordance with the SIM information of thefirst UE, wherein the first packet is destined for the first network.19. The first UE of claim 18, wherein the instructions further compriseinstructions to: receive a first packet, from the first network, afterreceiving a message indicating that the first UE has been added to afirst network, and transmit the first packet to the second UE, whereinthe first packet is destined for the first network.
 20. The first UE ofclaim 18, wherein the first packet is a voice packet.
 21. The first UEof claim 18, wherein the first packet is a data packet.
 22. A methodcomprising: receiving, by a first user equipment (UE) from a second UE,an international mobile subscriber identity (IMSI) of a subscriberidentity module (SIM) card of the second UE; registering, by the firstUE, the second UE to a network by transmitting the IMSI of the SIM cardof the second UE to a communications controller; receiving, by the firstUE from the communications controller, a packet using the SIM card ofthe first UE, after registering the second UE to the network; andtransmitting, by the first UE to the second UE, the packet in accordancewith the IMSI of the SIM card of the second UE.
 23. A method comprising:transmitting, by a first UE (user equipment) to a second UE, aninternational mobile subscriber identity (IMSI) of a subscriber identitymodule (SIM) card of the first UE; receiving, by the first UE from thesecond UE, a message indicating that the first UE has been added to anetwork, after transmitting the IMSI of the SIM card of the first UE;and receiving, by the first UE from the second UE via the network, afterreceiving the message, a packet, in accordance with the IMSI of the SIMcard of the first UE.